Investigation of seemingly random and gruesome killing in Denver area raises questions about public safety

A murder investigation at an apartment complex in the southern part of the Denver metro area left many in the community in the dark and questioning their safety. It happened in Lone Tree in early September.

A woman named Kathleen Mayo was found dead in her unit at the Aspect Apartments. Police released few details but assured the public there was -- in the department's words -- "no known danger." Five days later, Troy Marcus Reynolds, a tenant of the same complex, was arrested.

CBS Colorado obtained the suspect's arrest warrant. It revealed a disturbing timeline that shows what police knew and when.

According to the warrant, Reynolds, who faces a first-degree murder charge, told investigators he was a fan of "Dexter," a TV show about a serial killer. He described himself as reclusive and that he spent most of his time playing violent video games and interacting with others only on social media. He had meals and groceries delivered to his home.

He lived just upstairs from the 57-year-old victim.

"I've never seen his face ... because I looked to see if I'd seen this person around," said a neighbor named Madisson, who lives next door to the unit Mayo lived in.

"They said it was suspicious, and that was all we got -- but that we were safe," she said.

Symbol found written in blood at crime scene

The warrant in the case states Kathleen Mayo was last seen walking her two dogs on the apartment property on Aug. 24.

It wasn't until Sept. 4 -- after family members called for a welfare check -- that police found her body.

The warrant says at that time they saw "two distinct lacerations" on the victim's neck and her "left hand appeared to be possibly missing." Additionally, a symbol was found on the door of the victim's bedroom, described in the document as "a circle, with two distinct dots and a straight line under, similar to a 'smiley face' image. The symbol was confirmed to have been drawn with blood."

The next day, on Sept. 5, police posted on Facebook calling the death a "suspected homicide" but that there was "no known danger to the public."

Lone Tree officials emailed CBS Colorado the same statement and a second email that said, "as a follow up, there is no known danger to the public."

Two days after the body was discovered, the warrant says, a resident of the apartment building called police to report several drawings in the hallway and on the victim's door.

"There were way more, like, bigger spots ... and then, like, right here, there was a huge one," Madisson said about what she thought was blood on the hallway walls outside of her apartment.

The court document says police believed it was the same symbol found in Mayo's apartment. And because no information about the symbol was shared with the public, they believed "the unknown suspect had returned to the crime scene." They now believe the symbols in the hall were drawn in an unknown substance that could have been ketchup or BBQ sauce.

On Sept. 7, residents received an email from property management notifying them of the investigation. That same night, Reynolds called 911 several times and allegedly said at one point "The 57-year-old (woman? That) was me. It's obvious."

Reynolds was detained, questioned, then released

Reynolds was then detained and questioned.

Police searched his home and collected a 9mm handgun, 13 large knives and an autopsy saw.

He claimed to have been drinking when he called dispatch, and denied having any involvement in the murder.

Reynolds was then released and returned to the apartment complex where -- according to the police arrest warrant -- investigators began surveilling him.

On Sept. 8, Lone Tree police issued a second notice on their Facebook and to the media confirming the death was a homicide and released Mayo's name as well as her part-time role as an Uber or Lyft driver. There was no mention of any risk to the public.

"We got a little info from either online or, like, a little bit the police could give us when they were talking to me." Madisson said.

"I don't know. It feels like they shouldn't have been telling us that we were like totally safe," she added.

On Sept. 9, Reynolds was arrested and held on an unrelated charge. According to the arrest warrant, he was asked about the autopsy saw found in his apartment. He claimed to be a collector.

The investigator questioning asked if it was bought for a specific reason and the affidavit says Reynolds laughed and says no.

 On Sept. 12, Lone Tree police announced they had their suspect, and that Reynolds had been charged with first-degree murder.

Lone Tree police respond to questions about "no known danger"

CBS Colorado asked Lone Tree police about the decision to tell community members there was no known danger -- even as evidence pointed to a brutal killing, steps away from residents and an unknown suspect for several days.

In a statement, a spokesperson said in part: "At the time, it wasn't confirmed whether this was a homicide, and there was no evidence suggesting any danger to the residents or the public. The information we had indicated this was an isolated incident."

Lone Tree police chief Kirk Wilson also issued a statement:

"Our officers were on scene every day -- talking with the property management, interviewing every resident, collecting video, and following up on leads to identify and arrest the person responsible. I understand people want information as things unfold, but with an active homicide investigation, we simply can't share every detail without risking the case or the court process. At the end of the day, an arrest was made, and we believe we have the right person behind bars."

Troy Marcus Reynolds is being held without bond and is scheduled for a preliminary hearing in December.